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<table width="100%" summary="page for P.promelas"><tr><td>P.promelas</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Effect of sodium pentachlorophenate on growth of fathead minnow</h2>

<h3>Description</h3>

<p>Fathead minnows (<em>Pimephales promelas</em>) were exposed to sodium pentachlorophenate
concentrations ranging from 32 to 512 micro g/L in a 7-day larval survival and growth test.
The average dry weight was measured.
</p>


<h3>Usage</h3>

<pre>data(P.promelas)</pre>


<h3>Format</h3>

<p>A data frame with 24 observations on the following 2 variables.
</p>

<dl>
<dt><code>conc</code></dt><dd><p>a numeric vector of sodium pentachlorophenate concentrations (micro g/L).</p>
</dd>
<dt><code>dryweight</code></dt><dd><p>a numeric vector dry weights (mg)</p>
</dd>
</dl>



<h3>Details</h3>

<p>The data are analysed in Bruce and Versteeg (1992) using a log-normal 
dose-response model (using the logarithm with base 10).
</p>


<h3>Source</h3>

<p>Bruce, R. D. and Versteeg, D. J. (1992) A statistical procedure for modeling continuous toxicity data,
<em>Environ. Toxicol. Chem.</em>, <b>11</b>, 1485&ndash;1494.
</p>


<h3>Examples</h3>

<pre>

## Model with ED50 on log scale as parameter
p.prom.m1&lt;-drm(dryweight~conc, data=P.promelas, fct=LN.3())

plot(fitted(p.prom.m1), residuals(p.prom.m1))

plot(p.prom.m1, type="all", broken=TRUE, xlim=c(0,1000))
summary(p.prom.m1)
ED(p.prom.m1, c(10,20,50), interval="delta")

## Model with ED50 as parameter
p.prom.m2&lt;-drm(dryweight~conc, data=P.promelas, fct=LN.3(loge=TRUE))
summary(p.prom.m2)
ED(p.prom.m2, c(10,20,50), interval="fls")

</pre>


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